Motor control.



A. SUNDH.

MOTOR CONTROL APPLICATION FILED DBG.17, 190B 1,01 1,268. Panted 111111124911.

SHEETS-SHEET 14 A. SUNDH.

MOTO?b CONTROL,

APPLCATION ILED DEG.1'/, 19084 1,01 1,268.

Patented DOO. 12, 1911.

6 SHEBTS-SHEBT 2.

me/mim mi; www

A. SUNDH'.

MQTOBl GONTRGL.

APPLICATION FILED DE0.417, 1908.

1,01 1,268. Patented' Dec. 12, 1911.

6 SHEETS-SHEET 3.

A. SU'NDH.

MOTOR CONTROL.

APPLIUATION FILED No.1?. 1908.

1,-01 1,268. Patented Dec. 12, 1911.

6 annimmm 4.

1 nl Hanuuumwl 3yr/vento@ A. SUNDH.

MOTOR CONTROL.

APPLIUATION FILED 1320.17, 1908,

1,01 1,268. Patented 981112,191'1.

6 SHEETS-'SHEET 5,

A, SUNDH. MOTOR CONTROL.

APYLIOATIO'-E'ILBD DE01?, 1908.

1,011,268. Patented Deo.12,1911.

6 SHEETS-SHEET 6,

AUGUST SUNDH, F YONKERS, NEW YORK. I

Moron CONTROL.

Specification of Letters Patent.

y Application led December 17, 1908. Serial No. 468,012.

'o all whom it may concern:

Beit known. that I, AUGUST SUNDH, a

- citizen of the United States, residing in Yonkers, in the county of Westchester and State of New York, have invented a new and useful Improvement in Motor Control,

y of which thefollowing is a specification.

My invention relates to improvements in controlling devices for electric motors, and one of its objects is the provision of self-contained, practical and efficient means for controlling the operations of starting, stopping, reversing, and accelerating alternating current or other motors, more particularly those used in operating electric elevators or other hoisting machinery.

Generally speaking, my invention 4comprises 'means whereby a motor is started, stopped and reversed by means of manually operated rcontact devices, such as push-buttons, the acceleration of the motor to full normal speed in either direction being effected by means of a series of mechanically operated switches which are controlled in their movements by the motor itself through the medium of a magnetic clutch device and intermediate mechanism.

Other objects of the invention will appear hereinafter, the various novel features of construction being set forth in the following detailed description taken in connec` ventiOn; Fig. 2 is a sectional side elevation taken on the line a-a of Fig. 1; Figs.-,3, 4 and 7 are detail views of various parts of my apparatus; Fig. 5 is a sectionalside view taken on the line bofv Fig. 1; Fig. 6 is a -sectional'view on the line @we of certain parts shown in Fig. 3; Fig. 8 shows a typical electric elevator system embodying my invention; and Fig. 9 is a wiring diagram of the electrical circuits therefor. x

Referring to Figs. 1 and 2, 12 designates a metal frame-work to which is attached an insulating base 11, preferably. of slate or marble", upon which the various electrical and mechanical parts aremounted. At-the upper part of the insulating base 11"I are mounted vtwo similar 'reversing switches 1,3

and 13. Each of these switchea comprises a switch arm 14 which is pivoted at 15 to a Patented Dec. 12, 1911. l"

bracket 16 secured to the base 11. At the upper end of the switch arm 14 are' shown insulated contacts 18, and, while any desired number of such contacts may be carried by the switch arm, in the present instance there are but three.

, 6o Suitable flexi-v against a downwardly extendlng portion of the switch arm 14 and tends to swingv the arm about its pivot 15, thereby causing the contacts 18 to electrically engage corresponding `spring-pressed stationary' fixed contacts 63 in alineinent therewith.'

26 and 25 designate a magnet frameand windingv therefor, respectively, which are suitably mounted upon the back of the base 11 and arranged to co-act with a magnet armature 27 carried by a lever 22. The latter is pi'voted' at 2 1 to the bracket 16 and is adapted'to engage the roller 23 pivoted' at 24 to the switch arm 1.4. Since the-lever 22 and connected armature 27`are massive in 'Y form "and have considerable weight, they" rocker arm 9 (Fig. 1) of suitable dimensions ispivoted to a stationary bracket 10 located between the reversing switches 13 and 13'.'I andgwhose function is to prevent both of the switches 13and 13 from being closedat the same time, the rocker arm actingas a mechanical interlocking device .A sprocket wheel 8 is secured to a shaftif 7 which extends. the full width of the controller and is adapted to freely turn in suits able bearings 6, 6 mounted upon either side k of the controller framework 12. The shaft v7 will tend to swing downwardly and eXertff carries upon it a magnetic clutch device32 v`10C a sleeve 31 which carries the cams 35, 3.6,.

37, 38 and 39, a centering spring 30andfa 'spur gear- 28. Suitable collars j 33 andf29l.; are secured tothe shaft'7 near either end `b .means of the set-screws 34 and 40, respee 10 tively, which limit the end play of rounds the shaft 7.

various parts carried upon the shaft 7. The magnetic clutch device 32 1s clearly shown in Fig. 4 and comprises two clutch members 41 and 50. The latter may be integral with the cam sleeve 31, as shown, or a separate part connected thereto. The peripheral surface 53 of this clutch member 50 is tapered so as to correspond with the corresponding tapered surface 54 of the other clutch member 41 adjacent thereto. The clutch memberplace by means of the collar 48 and set-screw' therefor. A compression spring 49 surrounds the shaft 9 and lies in a recess 56 formed in the clutch member 41 and sur- The function of this spring 49 is to force the clutch members 41 and 50 out of engagement with each other at their co-acting tapering cont-act surfaces 54 and 53, respectively, except atsuch times as the magnet winding 46 is energized. The engaging surface 53 of the clutch member 50 containsl at equidistant points thereon a number ofjholes which are parallel to the axis of the shaft 7, and each contains a Wedge-shaped plug 51 which is tapered to correspond to the clutch engaging surface 53 and which is pressed outwardly by means of a spring 52. These spring-pressed tapered plugs 51 not only assist the spring 49 to force the clutchmembers out of engagement with each other, but also insure that the clutch surfaces 54and 53 will engage each other fair and true whenever they are brought into contact.

57,'57 designate suitable brushes which bear against the slip rings 44, 44 and by means of which current is supplied to the magnet winding 46. These 'brushes have suiiicient width to allow a small horizontal movement of the slip rings 44, 44 without the latter being carried out of electrical engagement therewith.

As before pointed ont, the cam sleeve 31 is loosely mounted on theshaft 7 and may be made hollow as shown in Figs. 4 and 6, so as to reduce its weight. This cam sleeve contains tive cams 35, 36, 37, 38 and39. The first four cams are equally spaced from each other and of varying size. The cam 39 is arranged on the sleeve 31 at an angle of 160 degrees from the cams 35, 3G, 37 and 38, and at a suitable distance therefrom.

The normal position of the sleeve and cams is as shown, and in order to maintain it in this position a centering device is provided. This device is shown in detail in Fig. 6, and comprises an arm 60 connected to the sleeve 31 and having a pin 61 secured thereto which lies between the ends 59, 59 of a centering spring 30. This spring loosely surrounds the sleeve 31 and has its ends bent outwardly so as to embrace the pin 61 and a fixed stop 5S which is bolted in position upon the base 11. Any rotation of the sleeve 31 in either direction causes the pin 61 to'tighten the coils of the spring 30, which thereupon exerts a strong react-ion tending to return the sleeve back to normal position. A spur gear 28 is keyed or otherwise securely fastended to the shaft '7 adjacent the cam sleeve 31l The cams" 35, 36, 37 and 38 are adapted to operate similar resistance controlling switches 62, 63, 64 and 65, respectively.

These switches are in many respects similar to the reversing switches 13 and 13. Each comprises a swinging arm 66 pivoted on a rod 67 which is supported by a bracket 83, and carrying two insulated contacts 69 and 70 vertically arranged at the upper end, which are adapted to engage corresponding fixed contacts 71 and 72, respectively, carried by a holder 85 which is pivoted at 73 to a stationary bracket 75. Springs 74, 74 tend to maintain the contacts 71 and 72 and the holder 85 in a vertical position, but allow the latter to adjust itself when the switch 62 is closed so as to insure a good electrical contact between the contacts 69, 71 and 70, 72, respectively. Suitable ilexi-V ble conductors connect the movable contacts 69 and' 70 to the terminals S7 and 8G, respectively. Each switch is normally held in open position against the action of a compression spring 68, one end of which bears against an extension 88 to the switch arm 66; the other end extends through the base 11 and bears against the bracket S4. Interposed between-a lug 76 upon each switch arm and the cams 35, 36, 37 and 3S are bell crank cam levers 89, 90, 91 and 92, respectively. These cam levers are all carried upon a common pivot rod 77 supported by the bracket 84, and each lever, such as 92, carries a cam roller S1 upon one end which engages the corresponding cam'3S, while the other end 73 passes through the base 11 and engages the lug 76 of the corresponding switch 62. rl`hus it is seen that as long as the cam rollers are in engagement with their respective cams the corresponding switches will be held open against the action of the switch closing springs, such as 68. A stop 79 is secured to thc base 11 and arranged in the plane of rotation of the cam 37 and is for the purpose of limitinv the rotation of the sleeve beyond a certain point,

-sjui'table means, and rotates therewith.

tratase 13e.

65 formed integral with cams 133 pwoted which in the present instance is somewhat less than 180 degrees.A At thelower part of the base" 11-l are a number of similar magl netically operated switches 97, 98 and 99.

Each comprisesa magnet Winding 96 adapt y edl when energized to' move a pivoted switch arm 93 so as to .connect the contacts 94 and l v95 carried the switch armand the base 11, respectively.'

,Referring nere `particularly 'to Fig. 5,'it will be seen that! the switch 100 is in many respects similar to the reversing switches 13 and 13. A. switch arm 104 carries at i"the upper end two contacts, such as 101, 15 which are .adapted to engage corresponding fixed contacts, as 102, when the switch arm is `moved into closed position by means of n compression spring 110. `Other contacts, it 103, are `also brought into electrical. en gagement withI each other upon closing the switch, while still other contactsll/l which are normally in engagement are separated p and any electrical circuit therethrough interrupted. The magnet 107 when ener- 2.5 giz'ed raises the armature 108 and lever 113, the latter swinging about its pivot 109 out of engagement with. the roller 112 and ailowing the spring 110 to force the switch closed. The lever 113 has anupwardly einm tending portion 105 which engages one arm' 10G of a bell crank lever which extends through'the base 11 and is pivot-ed upon the rod 7 i. y The other arm 116 of this lever 't carries a roller 117 which is arranged to be 36 engaged by the cam 39 when the same is rotated into engagement therewitlnvthereby depressing the arm 116 and forcing the arm 106, together with the lug 105, outwardly.

" n this manner the armature 108 'and con- 49 nected lever 113 are raised and the switch 100 is enabled to close its contacts. The spur gear 28'which is secured to the shaft 7 and rotated therewith, meshes with a larger gear 115 which is rigidly connected to'a'shaft 119 and gear 118, the latter gear being in mesh with a large gear wheel 120. This gear wheel is securely fastened to a shaft- 121 by means of a pin 120, or othr 50 number of arms 122, 123, 124 and 125-'a1e adjustably mounted upon the shaft 121', and secured in proper 'position bymeans of setscrews, or otherwise. These arms are provided with rollers, such as 126, which are comprise a series of contact arms such' as 80 131 `carrying contact rollers 129 at their outerends which are adapted to be moved into 'and out of engagement with coperatirgcontacts 130 secured to the insulating The arms 1' are carried byI or the shaft 127 in position to'be operated by the rollers 126 cn the arms 122, 123, 124 and- 125. Al stop rod 128 limits the movement. of the several Contact arms and connected cams in both directions. This circuit con trolling apparatus C is commonly known as a loor controller. f

represents 'the' motor starting resist ance and is preferably made up of a number of cast iron grids which are mounted upon insulated rods 136, 136secured to the frame work 12 by means of bracl'rets' 137; Other forms of resistance may be used, if so de-I` sired, the type shown being the preferred form, owing to. its compactness,,cheapness andeiiiciency.. v

Fig. 8 illustrates diagrammatically a typicat electric elevator system embodying my invention, in which M designates a hoisting motor which is connected through* the usual gearing contained in the gear case G to a hoisting or Awinding drum D. Cables 4 and 5 are wound about the drum D, the cables 5 being connected to theelevator carr K while the; cable t is connected to a counterbalance weight W. Suitable, guide pulleys P over which the cables l and 5 pass are* carried by bearings supported on the over-l head beams O. vThe sprocket wheel 8 of the controller C is connected by a sprocket chain S to a sprocket wheel 138 mounted uponthe drum shaft. While this connection is the preferred one, the sprocket wheel 8 may be connected to any desiredmoving part of the elevator'system, provided that the shaft 7 of the controller C is rotated in synchronism with the traveling elevator car.` The operation of the apparatus thus 'far described is as follows: Upon `closing a cir-' cuit through the magnet winding 25, the 105 armature 27 and connected lever 22 are lifted, the latter swinging about its pivot 21 and away from the roller 23 carried by the switch -arm 14, thereby permitting the spring 17 to close the switch 13. Upon closing this switch, the motor and hoisting apparatus are set in motion and the sprocket wheel 8 connected thereto by the` sprocket y chain S wili slowly rotate, Upon closing a circuit to the motor a circuit is also vclosed to the magnetic clutch 32 and the ysaine is energized .to move the clutch lmember 41 into frictional engagement with the clutch member 50. The sleeve 31 land connected cams 35, 36, 37, 38 and39will nowrotate 120 against the action of the centering spring 30. As the sprocket wheel 8', together with the shaft 7, clutch 32 and cam sleevel 31, continues to rotate, the cam being vthe .smallest is iirst moved out of engagement with-the corresponding cam roller 81. The.

Vspring 68 is now able to close' the switch 65 and at the same time litt thel swinging leverl CSQ-and cam roll-er 81. its the sleeve 31 continues to rotate, the with run 136 ott' its corresponding cam roller and the switch ('34 will be closed. ln a similar manner the switches 03 and 02 are closed successivcly as the cams 3T and 38 are rotated ont of engagement with their respective cam rollers. The switches G5, 64, 63 and 62 are connected to the motor starting resistance and their successive closing effects .the gradual acceleration of the motor to full speed as hereinafter described. At about this time the cam 39 engages the cani roller 117v and forces the latter downwardly, causing the lever arm 10G to bear against the lever 105 and thrust the latter outwardly. This operation swings the lever 113 and connected armature 108 about the pivot 109 and out of engagement with the roller 112 carried by the switch arm 104, thereby per niitting the spring 110 to close the switch 100. As soon' as the switch 100 has closed, the circuit to the magnetic 'clutch 32 is interrupted at the contacts 114 and the same becomes denergized, thereby permitting the springs 49 and 52 to separate the clutch members 41 and 50. longer operatively connected to the rotating shaft 7 and is at once rotated back to its initial or normal position by means et the centering spring 30. As the sleeve 31 and connected cams rotateback to normal position, the cams 35, 36, 37 and 33 once more engage their respective cam rollers and the corresponding switches 65, 64, G3 and 62 are again moved into open position. At the same time the cam 39 is moved Vout of engagement with the cam roller 117 and the latter is free to move upwardly. This operation would effect the opening of the switch 100 were it not that the magnet 107 was energized by the closing of the switch contacts. 103 so that the switch 100 remains closed. I1" tor any reason the clutch 32 should tail to release its clutch members at the proper time, the stop 79 will eEect a positivestopping of the cam sleeve 31.

It is readily seen that the shaft 7 continues to rotate as long as the motor lll is in motion. Now, since the gear 28 is connected to the gear 120 through the train of reducing gearing comprising the gears 115 and 118, the gear 120, together with the shaft 121 and connected arms 122, 123, 124 and 125, will rotate at a much slower speed than that of the sprocket wheel 8. As these arms 122, etc., are thus slowly rotated in one direction or the other, depending` upon the direction of rotation of the hoisting motor M, the rollers thereon engage the corresponding cams, such as 133, to eect the opening or closing of the corresj'ionding switch contacts, such as 129 and 130. Y

Referring to the wiring diagram shown in Fig. 9, a, b and c designate conductors leading from a suitable source of three-phase The sleeve 31 is noI l alternating current supply, and L is a main line switch. The reversing switches 13 and 13' are shown diagrammatically, each comprising a leaf spring carrying a plurality of insulated contacts adaptedto engage corresponding iixed contacts arranged to cooperate therewith. The motor is shown as a three-phase motor with stator windings connected to the terminals 139, the rotor windings being connected through the slip rings 140 to a delta-connected motor starting resistance 135. The wiring diagram .represents an automatically operated pushbutton system of elevator control adapted to three floors, with the car at rest at the second floor landing. 1, 2, 3 and 1', 2', 3' designate the push-buttons inthe car and at the floor landings, respectively. d, d, d, designate the door contacts located at the several floors, while 141 is a normally closed safety switch in the car, by means of which the latter may be stopped at any point in its travel. Assuming the main line switch L closed and the elevator car in the position shown, all of the landing doors being closed, the push-button 3 is now pressed to bring the car to the third or uppermost floor. Upon pushing the button 3, a circuit 4is closed from the main a' through the wire 149, door contacts d, d, d, wire 150, safety switch 141, push-button 3, wire 152, through the magnet winding of the switch 99, floor controller contacts 146 which are closed at this time, wire 153, through the winding 25 of the reversing switch 13', and to the main b'. This circuit includes the windings of the magnet switch 99 and the reversing switch 13', and the same will be energized to close their contacts 94, 95

and 1S, 63, respectively. The closing of the contacts 94 and 95 establishes a self-holding circuit around the push-button 3 and the latter may now be released without interrupting the circuit just traced. The operation of the reversing switch 13 closes a circuit to the stator winding of the motor M and brake magnet B', and the hoisting machinery is set in mot-ion, running at slow speed since the starting resistance 135 is included in the rotor circuit. lThe magnet clutch 32 is energized at the same time that the motor receives current, since it is connected through the contacts 114 to the motor terminals. As the motor rotates at slow speed, the sleeve 31 and connected cams also rotateuntil the cam 35 moves out o1 engagement with its corresponding cam roller and allows the switch 65 to close. The closing of this switch short-circuits a portion of the starting resistance 135 and allows the motor to receive more current followed by a corresponding increase of speed. As the cams continue to rotate, the switch 64 is next closed, thereby slort-circuiting an additional portion of the starting resistance, and

the motor still, further increases its speed. In a similar manner the switches G3 and 62 are successively. closed, thereby short-circuiting further portions of the starting re-y sistance., about this time the cam 39 has rotated into a position to close the switch 100 which eects the closing of the contacts 101 and 102, thereby short-circuiting thofentire starting resistance and closing a circuit at the contacts 103 through the winding of the magnet 107 which becomes energized and maintains the switch 100 closed, The closing oit the switchlOO opens the contacts lili, thereby interrupting the circuit to the magnet clutch 32 and the lat-ter becomes denergized, thereby allowing the sleeve Sl and connected cams to be rotated back to their original position by means of the returning spring and again open the switches 62, 63, 64 and G5. The switch 100 remains closed, however, due to the energization of its magnet, and the starting resistance being entirely short-circuited, the motor attains full speed, the car traveling in an upward direction. As the car approaches the uppermost landing corresponding to the pushbutton 3, the floor controller has been r0- tated vinto suoli a` position that one of the arms carried thereby effects thes'eparation of the contacts 146 and interrupts the circuit including the 'magnet switch 99 and reversing switch 13 and they become deenergized and open their contacts. The deenergization of the reversing switch 13 cuts oil the current supply to the motor M, brake magnet windings B and magnet winding of switch 100. The brake B 'is now applied to stop the motor and hoisting mechanism, while the switch 100 opens and all parte come to rest with the elevator car opposite the thirdfloor landing. As soon as the car moves away from4 the second door, the floor controller operates to close the contacts 148, the contacts 148 remaining open:

Shouldthe button 'l or l be pushed to cause the car to travel to the first floor, the operation would be ,similar to that justlde-y scribed,"excepting `that a circuit wouldbe closed through the magnet switch 97', floor cont-roller contacts 147, andmagnet of reversing switch i3. The latter would energized and Aclose its contacts, thereby closing" a circuit to the motor M and causingit to rotate in an opposite direction and lower the elevatorl car, the door controller l automatically opening lthe operating c1rl cuits at the contacts 147 as lthe car reaches g the first door landing.l While the sleeve 31 and connected cams are rotated in a direction opposite to that produced whenthe ele vator car was ascending, the` switches f65, 64,63, 62 and 100 operate to close their contactssuccessively in sequence just as before, since the cams are symmetrically disposed with respect to the corresponding cam rollers. rest at any point in its travel ineither direction by merely opening the safety switch lei, the latter being intended for emergency use only since the floor controller automatically stops the car at any predetermined. landing without any interference.

Vhile the system of electrical circuits herein shown and described is adapted to' a three-phase alternating current automatic push-button control, the same could readily be modified to adapt it to other methods of control with either a direct or alternating current of any desired phase. Also, while the electrically operated switches herein shownare preferred over other types of switches, my invention is not limited to this particular form of switch.

lt is obvious that 'various modiiications could readily be made in the apparatus herein shown and described without departing from the spirit and scope of my invention, and for this reason I desire not to be limited to the precise construction and arrangement of parts disclosed.

What l claim as n'ew and desire to have protected by Letters Patent of the United States is i l. The combination withan electric motor, of a sectional starting resistance, switches for controlling said starting resistance, a clutch device mechanically connected to the motor and to said switches, magnetic means for operating said clutch device, and means operated by one of said switches for effecting a disengagement of the clutch members. Y i.

2. The combination with an electric motor, of a startingresistance, a plurality of mechanically operated switches for `controlling thel starting resistance, a shaft driven by\the motor, a clutch for operatively connecting said shaft to said switches,

magnetic means for operating the clutch upon starting the motor, and means operated by one' of said resistance controlling switches for e'ecting a disengagement of the clutch members. y.

The combination with an electric motor, of a plurality of accelerating switches, mechanical connections between the motor and said accelerating switches including anelect'romagnetic clutch, jmeans for simultaneously closing a circuitto the motor and clutch, and means operated by Vone of said accelerating switches forv opening circuit to the clutcha 4;. The combination with an electric motor, of a starting resistance, switohesfor controlling the circuits of said resistance, clutch device 'mechanically connected to the motor, switches for closingy a circuit to the motor, electrical means for operating the clutch Vuponsthe operation'V of one of the motor circuit closing switches` and The car may be brought to` means operated by one of the resistance conl trolling switches for edecting a` disengagetor, ot switches for controlling the starting, i stoppmg and reversing of said motor, a

plurality ot' accelerating switches, power transmitting mechanism between the motor and the accelerating` switches including a magnetic clutch device, means associated with one of the first named switches for effecting the operation ot the magnetic clutch device, and means operated by one of the accelerating switches for effecting a disengagement ot said magnet clutch device.

6. T he combination with an electric motor, of a plurality ot' accelerating switches, a cam memberjfor successivelyY operating said switches, mechanical connections between the motor and cam member including a magnetic clutch, means for ettecting an engager ment ot' the clutch upon closing a circuit to the motor, and means operated by oneot' said accelerating switches for eitecting a disengagement of the clutch at'ter the cam member has been moved a predetermined amount.

7. The combination with an electric motor, of a sectional resistance, a series of mechanically operated switches for controlling the resistance, a rotary cam member adapted to successively open or permitv the closure of said switches, a shaft geared to the motor, a magnetic clutch arranged to ope atively connect said shaft to the rotary cam member upon the closing ot a circuit to the motor, and means Jfor returning the rotary cam memberv to its original position after the resistance controlling switches have been operated -and while the resistance is shortcircuited.

S. T he combination with an electric motor, of starting resistance, a plurality oit accelera-ting switches for short-circuiting the starting resistance, a vcam member for operating said switches, power transmission mechanism comprising an electromagnetic clutch between the motor and said cam member, means for simultaneously closing a circuit to the motor and clutch magnet, means dependent upon the operation of one of said accelerating switches for opening the circuit to said clutch magnet, and means to return the cam member to initial position while the resistance remain; short-circuited.

S). T he combination with an electric motor, ol" a sectional starting resistance, a series of mechanically operated switches for controlling the resistance, a rotary cam member adapted to successively open or permit the closure of said switches, a shaft geared to the motor, a magnetic clutch arranged to operatively connect said shaft to the rotary cam member upon the closing of a circuit to the motor. means tor eti'cctmg i disengagement it ,saifl clutch upon the closing ot' one of said resistance controlling switches, i'neans tor returningsaid cam member to its original position upon disengagement ot' said clutch, and means for maintaining the starting resistance short-circuited independently ot the position ot the cam member.

l0. The combination with an electric motor, ot a plurality ot accelerating switches` mechanical connections between the motor and switches for ell'ecting the closing ot said switches, and electrical means for maintaining one ot' said switches closed.

ll. The combination with an electric motor, ot' a starting resistance theretor, a plurality ot' switches for controlling said resistance, mechanical means operated by the motor for successively closing said switches, an electromagnet comprising a magnet winding` associated with one of said switches and operable to hold the said switch closed,` means t'or closing a circuit to said winding upon the closing of said last-named switch, and means for returning the said mechanical means to initial position while the rsaid switch remains closed.

1Q. The combination with an electric motor, ot a plurality ot' accelerating switches, therefor, a cam member for e'lt'ecting the successive operation ot the accelerating switches, driving connections between the motor and cam member including a magnetic clutch, means for eecting an engagement of the clutch members upon closing a circuit to the motor, means operated by one of said accelerating switches for ettecting a disengagement of said clutch members, and permitting a return of the cam member while the accelera-ting switches remain operated, and means con'iprising a magnet winding in a branch to the notor circuit t'or maintaining the last named switch in closed position as long as the motor circuit remains closed.

13. The combination with an electric motor, of a starting resistance, switches arranged to successively short-circuit portions of said starting resistance, mechanical means associated with the motor for closing said switches, and electrical means associated with the last operated of said switches for maintaining the same closed while the said mechanical means is restored to initial position.

14. The combination with an electric motor, of a starting resistance therefor, switches arranged to short-circuit portions of said starting resistance, cam mechanism for eiecting the successive operation of said switches, a clutch device geared to the motor and arranged to operate said cam mechanism, means for etlecting an engagementof said clutch device upon closing a circuitto `a car, of an electricmotor, a Shaft, a sleeve th motormcans operated by one of said Switches for effecting a disengagement of clutch device, means to return the cani ilfchanism when the clutch device is'disengaged, and electromagnetic means for maintining' the last named switch closed as long fjas'the motor circuit remains clsed,

15. The combination Wit-li an electric motor, .of a. starting resistance, a plurality of switches for -short-circuiting portions of said resistance, mechanical means for effecting the successive closing of said switches, elec'- trical means for holding one of said switches Said motor by operating any one of said l,circuit-closing devices, a controller, accelerating and stop switches mounted upon said icontrollen mechanical connections between Said motor and controller for `positively operating said stop switches, and frictional driving means associated with said mechanialconnections for eifecting the operation bf said accelerating switches.

17. In an elevator, the combination with mounted on the shaft, cams carried by said sleeve, a clutch forming a driving' connec- #tion between the sleeve and shaft, a fioor controller geared to the shaft, driving connections bet-Ween the motor and shaft, accelerating switches operated by said cams, and means-for operating the clutch.

18. The combination of an electric motor, starting resistance, switches controlling said resistance.,- cam mechanism for operating said switches, `a train of gearing comprising a clutch between the motor and said cam `mechanism, means for operating said clutch 45t to connect the motor and cam mechanism,

' means to automatically release the clutch when' the switches have been operated, and

means to return the cam mechanism when the clutch is released.

19. The combination of an electric motor,

accelerating mechanism therefor comprising a series ofaccelerating switches, a shaft. a cam sleeve mounted thereon, cams on. said sleeve operatively associated with said switches, an electromagnetic clutch comprising clutch members connected to the said shaft and cam sleeve, respectively, and means to control the circuits for the motor and clutch magnet.

20. The combination of a shaft, 4a cam 60 sleeve mounted thereon, cams on said sleeve,

an electric motor, accelerating apparatus therefor controlled by said cams, an electro. magnetic clutch having its members connected tothe said shaft and cam sleeve, re-

spectively, and gearing connecting the' mo tor and said shaft.

2l. The combination of an electric motor, accelerating switches, a cam device for controlling the operation of said switches, an

electromagnetic clutch having its members connected to the motor and cam device respectively, means for energizing the clutch magnet and effecting the operation of the said switches, and means releasing the clutch 75 and returning the cam device when the said switches have operated.

22. The combination with a shaft, of a sleeve rotatable thereon, -a clutch having its members connected to the shaft-and sleeve,

respectively, means for operating the clutch, a plurality of switches, and means carried by the sleeve for eiecting the successive operation of said switches.

23. The combination with a shart, of a g5 sleeve mounted on the shaft, a clutch forming a driving connection between the sleeve and' shaft, means for operating the clutch, a series of cams carried by 'the sleeve, and

electric switches associated with said cams.

AUGUST SUNDH, Nit-nesses EDWARD A. FITCH, Jon Fieri, J r. 

